Methyl-Substituted Poly(vinylnaphthalene) as a Reversible Singlet Oxygen Carrier

Article abstract of DOI:10.1021/ja00308a028

Methyl-substituted poly(vinylnaphthalenes) (5a-c) were prepared by radical polymerization of the corresponding vinylnaphthalenes 4a-c.Polymers 5a and 5b have been shown to bind and release singlet molecular oxygen (1O2) reversibly at temperatures between 0 and 35 deg C.Methylene blue sensitized photooxygenation of polymers 5 at 0 deg C produced the corresponding polymer endoperoxides 6 in nearly quantitatve yields.Generation of 1O2 from the thermolysis of polymer endoperoxide 6b at 35 deg C was confirmed by trapping experiments using typical 1O2 acceptors.Kinetic parameters for the thermolyses of 6a and 6b were compared with those for the corresponding monomer endoperoxides.The yield of 1O2 generated from polymer 6b was determined to be as high as 66 +/- 5percent.The synthetic utility of these polymeric endoperoxides as a 1O2 source has been demonstrated in the oxidation of a series of representative substrates.Advantages of using these polymer 1O2 sources are the following: (1) the mild condition for generation of 1O2, (2) utility in nonsolvent systems, and (3) easy removal and resue.